Macbook Pro frozen and black screen!

The problem. My Macbook Pro has frozen whatever I do. Sometimes it's by using Logic Pro but other time when I only listen to the music. It's getting frozen and then turn off to black screen and white led in fron is lighting.
If I want to turn it on.. one time it's just black screen and still light is on, second time it's turning on and after doing nothing it's getting frozen again.

I have Macbook Pro 15 Mid 2010, 4gb RAM, 2,4 GHz Intel Core i5
I was in authorized service and they said that after 2 weeks nothing was happening and all test was fine and they bring it back to me. After one hour of using it get down.

here is some pic of error's has shown and some pic of screen at frozen moment:

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